Process for preserving juice



July27', 19 43. F. H. COLLINS 2,325,111

. PROCESS FOR PRESERVING JUICE Original Filed March 3, 1941 //v VENTOIQ Z fia/r/rHCo/fins Patented July 27, 1943 PROCESS FOR PRESERVING JUICE Frank H. Collins, Orange, Calit, assignor to California Fruit. Growers Exchange, Los Angeles, Calif., a corporation of California Original application March 3, "1941, Serial No.

381,447. Divided and this application Septemher 8, 1941, Serial No. 409,974

2 Claims.

The present application is a division of a. copending application Serial Number 381,447, filed March 3, 1941.

This invention relates to methods for storing and preserving fruit juices. More particularly, the invention relates to a method for maintaining fruit juices in substantially fresh condition.

Ordinarily fruit juices, and particularly citrus fruit juices, undergo various changes soon after their preparation. These changes occur more rapidly in some types of juice than in others, but in all cases where the changes do occur, they adversely affect the quality and taste of the juice from the standpoint of the consumer. Many factors contribute to this change in the juice, as, for example, those due to ferments, oxidation by air and light, as well as the temperature when considered with these factors.

A great deal of work has been done in an effort to minimize, if not eliminate, the effects of the various factors mentioned above. For example,

, fruit juices in substantially fresh condition for g fermentation, or bacterial changes are controlled by the addition of preservative, or by subjecting the juice to pasteurizing temperatures for sulficient lengths of time, or both. Unfortunately,

although the change in the juice due to fermentation may be eliminated, the addition of a preservative often adversely affects the flavor of the juice, and subjecting the juice to pasteurizing temperatures often may impart to the product a taste commonly spoken of as a cooked taste. Similarly, a great deal of attention has been directed to ways and means of minimizing or eliminating the efiects caused by oxidation. For example, it has been suggested that the separation of the juice from its natural place in the fruit should take place in the presence of an inert gas to the entire exclusion of air, particularly oxygen, and that air within the juice product should be displaced by means of an inert gas.

Now, it is true that the changes which a fruit juice undergoes after preparation hare been studied, and many methods have been proposed for minimizing the changes, but in all cases, the processes ultimately selected, or even suggested, are complex and involve steps which greatly increase the cost of preparation of the product, and correspondingly increase the cost to the consumer. Moreover, many such processes are of such a nature that much diificulty is encountered in attempting to have them put into practice by any except the most highly skilled workmen.

I have found that the above mentioned adverse changes in the juice can be effectively overcome by methods hereinafter disclosed. In general, my

invention comprises maintaining a body of freshly prepared juice at a temperature sufliciently low to prevent fermentative and bacterial action, and to reduce oxidative efiects. At the same time, I maintain the body of juice in constant non-turbulent motion and simultaneously sweep the air from the body of the juice. This may advantageously be accomplished by means of a device adapted to the performance of the process. Such means are illustrated herein.

Accordingly, an object of this invention is to provide and disclose methods formaintaining a considerable period after their preparation.

A further object of this invention-is to, provide methods for maintaining a fruit juice in condi-'- tion such that adverse changes in thejuice are I Fig. 2 is a horizontal section of thedevice taken along the line 2--2 of Fig. l, and showing the cabinet broken away.

Fig. 3 is a perspective view of the impeller. Corresponding and like parts are referred to in the following description and are indicated in all views of the drawing by the same reference numbers.

Referring now to the drawing in detail, it will be apparent that the device for practicing the invention which has been illustrated comprises a refrigerating cabinet l9, shown mostly broken away. Within the cabinet Hi is contained a suitable refrigeration mechanism, not shown. The cabinet l0 has, as an integral part thereof, a raised portion 9 on top within which is housed a cold plate i3 which may be refrigerated, for example, by means of gas expansion operating in conjunction with the refrigeration mechanism in the usual manner. The cold plate is surrounded on sides and bottom by suitable insulating material within the raised portion 9. Supported by the raised portion 9 of the cabinet containing the cold plate It, is removably positioned a container ll, having a hood l2. Said container is so positioned on the cabinet that the cold plate it is in immediate contact with device may be made in accordance of the same diameter. J to thecold plate I3, I find it convenient to have it,"ingenerahcorrespond to. the size .of the juice compartment ll. That is to say, if the cylincontainer ll, there is a juice compartment l4 completely separated from the sides of the container II by the insulation IS. The bottom of the juice compartment I4 is formed from a portion of the bottom of the juice. container ll. Through the side of the container H and the insulation I5 is a thermostat well i6 adapted to permit the placing of a thermostat unit in contact with the wall of the juice compartment M. A spigot I! is connected to the juice compartment Hi to permit the withdrawal of the juice. A motor 18 operating, if desired, in conjunction with a gear reduction device I9 is positioned on the juice compartment cover 20. Within 'the juice compartment I 4 there is centrally positioned an impelling device comprising a shaft 2! connected to the gear reduction mechanism l9, said shaft carrying vanes 22. In particular, it is desired to point out at this time that the vanes 22 are shaped in such a manner and are rotated in such a direction that there will be a gentle but positive movement of the juice from the bottom of the juice compartment towards the top of the compartment. The advantages to be obtained by constructing the impelling mechanism in such a manner will be discussed in more detail hereinafter. Fig. 3, which is a perspective view of the impeller, clearly shows the slight S- shape of the vanes and their arrangement on the shaft 2i so that the above-mentioned effect will be obtained.

The device illustrated in the drawing may be made in accordance with the following description. However, it is to be understood that many modifications in the type and kind of-materials used in the construction may be made without departing from the general principles set forth. For example, I choose to construct the juice compartment in a cylindrical shape, since I believe this shape is advantageous in that it permits me to effect a non turbulent movement of the juice within the compartment much more readily than a compartment of some other shape. In addition, the relative proportions and relationships of the various parts may be varied within comparatively wide limits. Accordingly, when speciflc dimensions are referred to, it is merely for the purpose of disclosing to those skilled in the art a satisfactory size. Such dimensions are to be taken as in no wise critical, but'the general relationships which they illustrate are important. I have found that a very satisfactory with the following dimensions. I

The rectangular refrigerating cabinet I0 may be of such size as to satisfactorily house the necessary refrigerating unit. A cabinet about thirty-two inches square and thirty inches high will adequately house one such available refrigerating mechanism. The raised portion 9 of the cabinet which houses the cold plate may advantageously be made the same shape as the 1 container H which rests thereon in order to inlit convenient to have the raised portion 9 housi'ng thecold plate also cylindrical in shape and Similarly, with respect drical juice compartment has a diameter of fourteen inches, then'I may preferably use a cythe bottom of the juice compartment will belindrical cold plate having a diameter of four- 1 teen inches. Such a correlation assures that evenly cooled since it will be in contact with the surface of a cold plate of at least the same extent. I have found that about three inches of good insulation between the juice compartment I4 and the container II is adequate to permitinsulation material.

With respect to the motor and gear reduction means, I have found it convenient to use a small electric motor of about one-fortieth horsepower having a speed of about 1600 R. P. M. The speed of the motor is then reduced by the gear reduction device to about 25 R. P. M. Obviously, other arrangements could be made to motivate the impeller, though I believe that it is important that a comparatively slow but continuous rotation of the impelling. device be obtained.

In particular, the impeller which I have found to be satisfactory in devices of the size above described is one in which the vanes 22 are each about ten inches in length and five inches wide. These vanes are, as mentioned before, slightly S-shaped." The extreme upper and lower ends of the vanes deviate about an inch from the vertical plane of the main portion of the vanes. The vanes are so arranged on the impeller shaft 2i and related to the direction of rotation of the impeller that they tend to lift the juice very gently from the bottom of the compartment towards the top, thereby assuring uniform cooling of the body of juice, as well as thorough, non-turbulent mixing of the juice. It is to be noted that the vanes "sweep through most of the space within the juice compartment so that the whole body of tory design.

I find it advantageous to have a thermostat unit in contact with the lower portion of the juice compartment, the thermostat automatically operating in conjunction with the refrigerating mechanism so as to maintain the temperature of the contents .of the juice compartment within a predetermined temperature range.

Although the materials with which my device can be made' ar variable within wide limits, I choose to have all parts which come in contact with the juice to be of a non-corrosive nature. In particular, I have found that stainless steel is very satisfactory, although glass or other highly non-corrosive materials may be used from which to construct the various parts coming in contact with the juice.

In the practice of my inventionwith the device juice which may or may not be chilled to within I a temperature range of about 32 to 34 F. The

. ture of the contents tends to rise above about 34 F., the refrigerating mechanism automatically starts and the content of the juice compartment is chilled to within the predetermined temperature range. peller in operation at all times that the device is in use. The juice may be withdrawn by means of the spigot I1 and additional juice may be added to the container as the need arises by merely removing the hood l2 from the container and the cover of the juice compartment and pouring in more juice.

Without attempting to enter upon any highly detailed theoretical explanation of the ultimate phenomena behind the results which I thus obtain, I desire to point out emphatically that fresh juice,

for example, fresh orange juice, handled by the I choose to have the immethodoutlined can be kept for days in-a condition such that experienced tasters of good sensitivity. can scarcely difierentiate it from freshly merit of the whole body of the juice cooperate to produce the most highly desirable results.

Iclaim:

' 1. A process for maintaining citrus juice in substantially fresh condition comprising maintaining the temperature of the juice within a range of from about 32 F. to. about 34 ,F'., and maintaining said juice in continuous non-turbulent movement, whereby the juiceis effectively deaerated and maintained in a relatively homogeneous condition.

2. A process for keeping citrus juice in a substantially fresh condition comprising adjusting the temperature of a body of freshly extracted juice to within a range of from about 32 F. to about 34 F., maintaining the juice within said temperature range and keeping the body of juice FRANK H. COLLINS. 

